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I've just installed 13.04 from scratch on a (very fast) machine that only has wired Ethernet. It looks as if it boots so fast that the Ethernet card can't keep up; it won't ever connect to the home LAN from a cold boot, but a reboot consistently solves the problem.

The machine is blazingly fast and goes from power-on to user desktop in less than ten seconds. I'm running an 8-core Intel i7 with SSD and 16GB RAM; the network card is some Intel gigabit card.

The machine is set up to log me in automatically, and Firefox is among the startup programs. Firefox always complains that it has no network connection because (even after a warm reboot) the network only connects a while after the user desktop appears. When the user desktop appears, there is a Unity popup that says "disconnected, you are now offline" and it is replaced by a "connected" popup roughly 20 seconds later.

This was not a problem on Windows.

1) Why doesn't the computer connect to the LAN until after the user login?
2) Why doesn't the computer connect to the LAN after a cold boot?

And obviously: How can I fix this?


  • I'm using my router's DHCP, not static IP.
  • Output of cat /etc/network/interfaces is as follows (when the computer has LAN connection):

# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback

  • Output of sudo ethtool eth0 is:

Settings for eth0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Speed: 100Mb/s
Duplex: Full
Port: Twisted Pair
Transceiver: internal
Auto-negotiation: on
MDI-X: off
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00000007 (7)
drv probe link
Link detected: yes

Note: the network should be gigabit, not just 100Mbps, but I haven't figured that one out yet either.

share|improve this question
I think more details as to the network setup may help, like are you using DHCP or static IP? NetworkManager or /etc/network/interfaces static configuration? Output of sudo ethtool eth0 perhaps? I suppose you care about startup speed and sleep 25 && firefox & is not an option for a partial temporary workaround? –  moon.musick Sep 1 '13 at 21:33
@moon.musick: I added the info you asked for. Your sleep 25 && suggestion is a neat trick, but the problem is that the network never appears after a cold boot; I must reboot the computer in order to get the network connection. And, yes, the network only connects after I've logged in - and that's pretty weird but not the central problem right now. –  Torben Gundtofte-Bruun Oct 5 '13 at 18:52

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